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101.
Studies have demonstrated a positive relationship between exposure and posttraumatic stress, but one's subjective appraisal of danger and threat at the time of exposure may be a better predictor of posttraumatic stress than more objective measures of exposure. We examined the role of peritraumatic response in posttraumatic stress reactions in over 2,000 middle school children 7 weeks after the 1995 Oklahoma City, Oklahoma, bombing. While many children reported hearing and feeling the blast and knowing direct victims, most were in school at the time of the explosion and therefore were not in direct physical proximity to the incident. Physical, interpersonal, and television exposure accounted for 12% of the total variance in our measure of posttraumatic stress when peritraumatic response was ignored. Peritraumatic response and television exposure accounted for 25% of the total variance, and physical and interpersonal exposure were not significant in this context. These findings suggest the importance of peritraumatic response in children's reactions to terrorism. These carly responses can be used to help determine which children may experience difficulty over time.  相似文献   
102.
柴胡皂甙q及其甙元的结构鉴定   总被引:4,自引:0,他引:4  
从小叶黑柴胡(Bupleurum smithii Wolffvar;parvifolium ShanetY.Li)的根中得到3个化合物,柴胡皂甙元A和Q及柴胡皂甙q。柴胡皂甙元Q和柴胡皂甙q为新化合物,根据理化性质和波谱分析,确定其结构分别为齐墩果烷-11,13(18)-二烯-3β,16β,23,28,30-五醇和3β,16β,23,28,3O-五羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基(1→6)-[α-L-吡喃鼠李糖基(1→4)]-β-D-吡喃葡萄糖甙。  相似文献   
103.
目的:对不同个体椎骨短期精度进行观察,发现骨质疏松的严重程度不同其短期精度不同。分析DPX-MD双能X射线骨密度仪测量不同个体椎骨骨面积、骨矿含量、椎体宽、椎体高的短期精密度,了解上述指标对骨矿含量或骨密度测定的影响,以便为骨矿含量或骨密度检测质量控制和减少误差提供依据。 方法:实验于2004-05/2006-12在川北医学院人体解剖实验室与川北医学院附属医院内分泌科骨密度室完成。①对象:铝体模;3个活体椎体(38岁骨密度正常男性;40岁骨质疏松症男性;62岁轻微骨量减少女性);1个带软组织的死体椎体(由川北医学院人体解剖实验室提供)。②方法及评估:采用美国Lunar公司生产的DPX-MD双能X射线骨密度仪测量各椎体的椎骨面积、骨矿含量、椎体宽、椎体高及骨矿含量/椎体宽。3次/d,连续测定5d。铝体模和死体椎体两端均用小木块固定在6.5cm的高度,放在15cm的水浴中,为减少误差由一人操作。由不同椎骨面积、骨矿含量、椎体宽、椎体高及骨矿含量/椎体宽可得到各自的变异系数。 结果:①腰椎各椎体和L2~4的骨矿含量的变异系数:各椎体或L2~4骨矿含量变异系数从正常男性椎体、骨质疏松症男性椎体、轻微骨量减少女性椎体与死体椎体呈依次增大。②各椎体和L2~4的椎骨面积、椎体宽、椎体高的变异系数:椎骨面积、椎体宽的值从铝体模、正常男性椎体、骨质疏松症男性椎体、轻微骨量减少女性椎体与死体椎体呈依次增大,尤其是轻微骨量减少女性椎体与死体椎体较大;椎体高的变异系数以骨质疏松症男性椎体与轻微骨量减少女性椎体较大,尤其是轻微骨量减少女性椎体的变异系数最大。 结论:不同个体椎骨骨面积、骨矿含量、椎体宽、椎体高的精度不同,对骨密度测定的影响不同。椎间隙欠清楚者由于椎体分椎线难于确定,椎体高度的测定对骨密度测定影响较椎间隙清楚者大;有骨质增生和骨质疏松越严重者由于椎体边缘线难于确定,椎体宽度的测定对骨密度测定影响较无骨质增生和骨密度正常者大;有骨质增生存在和骨质疏松越严重,骨面积的测定对骨密度测定影响越大;骨质疏松越严重,骨矿含量测定对骨密度测定影响越大。  相似文献   
104.
Twenty-six patients with progressive Hodgkin's disease after conventional chemotherapy received intensive chemoradiotherapy and autologous bone marrow transplantation (ABMT); 19 also received additional involved-field radiotherapy. Twenty-one patients [81%, 95% confidence intervals (CI) 61% to 94%] attained complete (n = 18) or partial responses. Ten patients (38%, 95% CI 20% to 59%) are disease- free a median of 4.5 years later (range 3.5 to 7.0 years), including seven patients with continuous complete responses. The likelihood of overall response was not significantly influenced by any clinical or treatment variable examined. However, there was a trend favoring patients with higher Karnofsky scores, and higher scores were associated with attainment of complete responses (P = .06 and P = .02, respectively, Mann-Whitney U test). Both higher Karnofsky scores and shorter durations of disease before transplantation were associated with improved survival in a stepwise Cox multivariate analysis. The chief cause of failure was progression at sites previously involved with Hodgkin's disease. No patient relapsed in the marrow, and two of three patients with a history of marrow involvement with Hodgkin's disease achieved durable complete responses after transplantation. These data suggest that inadequate pretransplant conditioning, and not the reinoculation of occult tumor cells in the autologous marrow, caused most relapses. Fatal treatment-related toxicity occurred in six patients. Three patients died of idiopathic interstitial pneumonitis; each had previously received local mediastinal irradiation before intensive chemoradiotherapy. Intensive chemoradiotherapy and ABMT produces durable responses in some patients with Hodgkin's disease incurable with conventional therapy. Use of such therapies at the first sign of failure with conventional chemotherapy and development of more effective conditioning regimens should further improve results.  相似文献   
105.

Purpose

Local anesthetic and corticosteroid combination injections are often used in clinical practice, however research investigating the chondrotoxic properties of these combinations is minimal. The goal of this study was to evaluate the effect of single injection doses of 1% lidocaine or 0.25% bupivacaine in combination with single injection doses of dexamethasone sodium phosphate (Decadron?), methylprednisolone acetate (Depo-Medrol?), betamethasone sodium phosphate and betamethasone acetate (Celestone? Soluspan?), or triamcinolone acetonide (Kenalog?) on human chondrocyte viability.

Methods

All treatment conditions were delivered to human chondrocytes in vitro for the medication’s respective average duration of action using a bioreactor containing a continuous infusion pump constructed to mimic joint fluid metabolism. A two-color fluorescence assay was used to evaluate cell viability. A mixed-effects regression model was used to evaluate the mean differences in cell viability between treatment groups.

Results

At 14?days, a single injection dose of 1% lidocaine or 0.25% bupivacaine in combination with betamethasone sodium phosphate and betamethasone acetate solution illustrated significant chondrotoxicity when compared with the local anesthetics alone (P?P?=?0.013; P?=?0.016, respectively) when used in combination with 1% lidocaine compared with lidocaine alone, but showed no significant chondrotoxicity in combination with 0.25% bupivacaine (P’s?=?n.s.).

Conclusions

Clinicians should use caution when injecting 1% lidocaine or 0.25% bupivacaine in conjunction with betamethasone sodium phosphate and betamethasone acetate solution due to its pronounced chondrotoxic effect in this study. 1% lidocaine used in combination with methylprednisolone acetate or triamcinolone acetonide also led to significant chondrotoxicity.  相似文献   
106.
Bone marrow from animals treated with 5-fluorouracil (5FU) competes equally with normal marrow when assessed in vivo in an irradiated mouse, but shows markedly defective engraftment when transplanted into noncytoablated hosts. Using Southern Blot analysis and a Y-chromosome specific probe, we determined the level of engraftment of male donor cells in the bone marrow, spleen, and thymus of unprepared female hosts. We have confirmed the defective engraftment of marrow harvested 6 days after 5FU (FU-6) and transplanted into unprepared hosts and shown that this defect is transient; by 35 days after 5FU (FU-35), engraftment has returned to levels seen with normal marrow. FU-6 marrow represents an actively cycling population of stem cells, and we hypothesize that the cycle status of the stem cell may relate to its capacity to engraft in the nonirradiated host. Accordingly, we have evaluated the cycle status of engrafting normal and FU-6 marrow into normal hosts using an in vivo hydroxyurea technique. We have shown that those cells engrafting from normal marrow and over 70% of the cells engrafting from FU-6 marrow were quiescent, demonstrating no killing with hydroxyurea. We have also used fluorescent in situ hybridization (FISH) analysis with a Y-chromosome probe and demonstrated that normal and post-5FU engraftment patterns in peripheral blood were similar to those seen in bone marrow, spleen, and thymus. Altogether these data indicate that cells engrafting in normal, unprepared hosts are dormant, and the defect that occurs after 5FU is concomitant with the induction of these cells to transit the cell cycle.  相似文献   
107.
Human platelets exert cytotoxic effects on tumor cells   总被引:6,自引:0,他引:6  
Ibele  GM; Kay  NE; Johnson  GJ; Jacob  HS 《Blood》1985,65(5):1252-1255
Monocytes are thought to play a role in host resistance to tumor cell growth in animals and humans. In addition, platelets are known to be involved in tumor metastases. To investigate the interaction of these two cell types and their effect on tumor cells, human monocytes and platelets were examined using an in vitro monocyte-tumor cell cytotoxicity assay. Monocytes alone resulted in 32% +/- 1.5 (mean +/- SEM) tumor cell kill. When platelets were added to monocytes in a 1:1 ratio, an increase in cytotoxicity to 61% +/- 3.2 was observed. The cytotoxicity noted when platelets were added to a fixed number of monocytes and tumor cells was dependent on the number of platelets added. A decrease in cytotoxicity from 32% +/- 1.5 to 12% +/- 2.3 was observed when contaminating platelets were removed from monocyte preparations. Platelets added to tumor cells in the absence of any monocytes were also toxic, resulting in a maximum kill of 95% at a 4:1 platelet/tumor cell ratio. Secreted products of freshly isolated platelets may be responsible for much of the observed cytotoxicity, since supernatants from the platelets were toxic for tumor cells. Platelets pretreated with a cyclooxygenase inhibitor (ASA) or a lipoxygenase inhibitor had decreased cytotoxicity compared with untreated platelets. Our results indicate that products of platelet arachidonate metabolism are toxic for tumor cell lines. They also suggest that the role of the platelet must be considered when studying monocyte-tumor cell cytotoxicity.  相似文献   
108.
During laparoscopic cholecystectomy (LC), cystic duct occlusion can be done with titanium clips or laparoscopically tied knots. However, till date, there is no randomized, controlled study reported in the literature that has prospectively compared the outcome using either of these methods. In the present study, 105 patients who were to undergo LC were randomly assigned to two groups. Group I comprised patients undergoing cystic duct occlusion with clips while group II comprised those undergoing cystic duct occlusion with knots. Our aim was to compare the postoperative outcome in both the cases. The incidence of overall bile leak following LC was 4 out of 105 (3.8%) while the leak rate following cystic duct occlusion with clips was 2 out 52 (3.9%), and that following ligature was 2 out of 53 (3.8%). The procedure using ligature took slightly longer time than that using clips. There was no significant difference in the postoperative outcome in either group. The use of ligature is a feasible, safe and cost-effective alternative to the use of titanium clips for cystic duct occlusion during LC.  相似文献   
109.
Jaffe  HS; Cadman  EC; Farber  LR; Bertino  JR 《Blood》1986,68(2):562-564
Pretreatment hematocrit in 117 advanced-stage Hodgkin's disease patients treated with a combined modality therapy program was evaluated as an independent prognostic variable with regard to survival and relapse-free survival. Age greater than 40 years, and multiple extranodal sites of involvement were found to be statistically significant independent negative prognostic factors with regard to survival. Pretreatment hematocrit, however, was not an independent negative prognostic variable.  相似文献   
110.
Heterotypic adherence between marrow stromal cells (MSC) and lymphoblastic cells is essential for normal lymphopoiesis and malignant lymphoblastic development. However, the detailed molecular mechanisms by which this heterotypic adherence occurs are poorly understood. The cell-cell interactions between a B-lymphoblastic cell line (UTMB-460) and a pre-B-cell line (NALM-6) with MSC were chosen as models to investigate potential mechanisms and adhesion molecules involved in the apposition between normal and malignant lymphoblastic cells and MSC. A parallel-flow detachment assay (PFDA) and a 51Cr detachment assay, coupled with monoclonal antibody (MoAb) blocking experiments, were used to quantify the attachment of lymphoblastic cells to confluent monolayers of MSC. The apposition between MSC and B-lymphoblastic cells (UTMB-460 cells) was investigated for variable time periods, ranging from 1 minute to 4 hours. Results from the temporal study suggest that the heterotypic adherence of the B-lymphoblastic cells to MSC is a biphasic event and the interactions occur rapidly (< or = 1 minute) after the two cells come into contact. More specifically, the early phase of adherence (< or = 15 minutes) solely involves very late antigen-4 alpha (VLA-4 alpha)/vascular cell adhesion molecule 1 (VCAM- 1) interactions, as evidenced by the nearly complete inhibition (93%) of UTMB-460 cell adherence in the presence of anti-VLA-4 alpha. The late phase (> or = 30 minutes) proceeds despite the continuous presence of anti-VLA-4 alpha. In addition, the late-phase adherence is not affected by MoAbs to LFA-1, CD44, VCAM-1, E-selectin, or L-selectin, which suggests the possible involvement of other adhesion molecules. Adherence of pre-B-lymphoblastic cells (NALM-6) to MSC is also biphasic. Integrin VLA-4 is again a major player in the early phase of pre-B-lymphoblastic cell/MSC interactions. The early phase of adherence may be important in homing of the malignant lymphoblastic cells to the MSC and the late phase in retention of malignant lymphoblastic cells in the bone marrow.  相似文献   
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